I am by no means a professional UW photographer, but a few tips I have learned have helped me get a small handfull of good shots.
The first is spot-on buoyancy. You have to be very good at holding your depth steady while you concentrate on setting up the camera and waiting for that perfect shot. Good camera skills mean nothing if your ramming into coral drifing out of range, or missing shots because you have to fin back into postion.
The next thing I learned was you have to be close. Real close a lot of the time. Which is hard when you have skiddish creatures that dont like the sound of bubbles. 6 feet in most circumstances is just about too far. Anything from 3 feet down to inches greatly increases your chances of getting a good shot.
Lighting is one of the biggest keys to good shots and there are TONS of variables to consider. Visibility, particles in the water, depth, available sunlight, the number and type of strobes, and many many more things that I still dont know about all come into play in UW photography. You can sum a lot of it up to depth. Of course the deeper you go, the less of the color spectrum you have available to you without the use of strobes/spots. Depth(and visibility) also limits the amount of usable light you have to make a shot work. I was told that for a novice photographer thats just getting started in UWP to start looking at two things.
STROBES/SPOT LIGHTS- If your using spot lights to light up your shot, make sure that the spots flood the focal point of your camera. If your subject is a little off-center and your lights arent hitting the subject, then of course things arent gong to turn out perfectly. As for the flash, a lot of people make the mistake of just aiming that flash straight at the subject. That reflects the light at right or near right angles to the camera. This lights up the particles in the water and can create a cloudy or muddled shot. The higher the visibility, the less the particles are an issue. When your using a flash, get it as far from the camera as you can so that the light hitting the subject doesnt reflect back at the camera. to get the idea, stand in front of a mirror and shine a flashlight at it. the closer the light is to you the more likely you are to blind yourself with the reflected beam. But with your arm stretched out you can clearly see the reflection of the beam on the glass without burning out your retinas. the flash works the same way. You want to see the lights hitting the target not the camera. this will unlock the details and colors on those fish and coral.
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